B.Sc is three years duration course whether it is regular mode or distance mode. If you are BSc graduate then you can do BTech in 3 years rather than 4 years but if you are BTech graduate than no institute offer 2 years BSc course.

Following are the list of best and top B.Sc Colleges in India --

Acharya Nagarjuna University, Department of Education
Aditya Degree and PG College
Akkineni Nageswara Rao College
ApTechnology Computer Education
Auroras Technological and Research Institute
Badruka Institute of Foreign Trade
Birla Institute of Technology and Science
C V S R College of Engineering
Centre for Distance Education , Acharya Nagarjuna University
Centre for Distance Education , University of Hyderabad
Centum Learning Limited
Dantuluri Narayana Raju College
DRK Institute of Science & Technology
Gandhi Institute of Technology and Management
Gayatri College of Science and Management
Indian Institute of Management and Commerce
JB Institute of Engineering College
Nagarjuna University , Faculty of Engineering
National Institute of Technology
Nizam College
Pragati Mahavidyalaya Degree and PG College
Rajiv Gandhi Degree College
Ramee Academy of Catering Tourism and Hotel Manage
Sir C Ramalinga Reddy College
Government City College
Indian Institute of Technology
Jahnavi Degree and PG College
Sri Yerramilli Narayanamurthy College
VSM College of Engineering
A. B. V. Government Degree College
A. S. D. Government Degree College for Women
Annam Guravamma Krishna Murthy College
Arts & Science College for Women, Andhra Mahila Sabha
Bhagavantham Gupta Bangaru Seshavatharam Women’s College
C. S. R. Sarma College
Ch. S. D. St. Theresas College for Women
Chaitanya Degree College
Chaitanya Post,Graduate College
Chatrapati Sivaji Tri Satajayanthi Government Kalasala
Church of South India: Diocese of Medak Wesley Degree College
D. R. Goenka Government Degree College
D.K. Government Degree College for Women
Dr. B. R. R. Government Degree College
Dr. Kotha Raghuramaiah Memorial Degree College
Dr. V. S. Krishna Government Degree College
Gayatri Vidya Parishad Degree College
Girraj Government College
Government Arts & Science College
Government College for Men
Government College
Singareni Collieries Women’s Degree College
Smt. Kandukuri Rajyalakshmi College for Women
Smt. Kondepati Sarojini Devi Mahila Kalasala
Smt. N. P. Savithramma Government College for Women
Smt. Velagapudi Durgamba Government Degree College for Women
Sree Anantha Padmanabha Arts, Science & Commerce College
Sree Konaseema Bhanoji Ramars College
Sri A. S. N. M. Government Degree College
Sri Dasari Narayana Rao Government College for Women
Sri Gurajada Apparao Government Degree College
Sri Kasu Brahmananda Reddy Government Degree College
Sri Padmavathi Mahila Hindu Kalasala
Sri Padmavathi Womens Degree College
Sri Sai Baba National Degree College
Sri Subbaraya & Narayana College
Sri V S Sivalingam Chettiar Government Degree College
Sri Valli Subrahmanyeswara Swamy Arts & Science College
Sri Vasavi Kanyaka Parameswari Arts,Science & Commerce College
Sri Velagapudi Ramakrishna Memorial College
Sri Venkateswara Arts College for Men
Sri Venkateswara College
Sri. A. B. R. Government Degree College
Srimathi Kasu Raghavamma Brahmananda Reddy College
St. Anns College for Women
St. Josephs College for Women
Subbarami Reddy & T. Balarama Krishna Degree College & P.G. Centre
Tara Government College
The Adoni Arts and Science College
The Bapatla College of Arts and Science
Tikkavarapu Rami Reddy Government Degree College
University Arts & Science College
V V & M Aided Degree College
V. R. S. & Y. R. N. College
V. S. R. Government Degree College
V. V. Giri Government Kalasala
Vemulapalli Kodanda Ramaiah College
Visakha Government Degree College for Women
Viswa Kavi Vemana Government Degree College
Y. A. Government Degree College for Women