156: There are 50 students admitted to a nursery class. Some students can speak only English and some can speak only Hindi. 10 students can speak both English and Hindi. If the number of students who can speak English is 21, then how many students can speak Hindi, how many can speak only Hindi and how many can speak only English ?
(a) 21, 11 and 29 respectively
(b) 28, 18 and 22 respectively
(c) 37, 27 and 13 respectively
(d) 39, 29 and 11 respectively
157: Among living organisms, which one of the following is the most responsible factor for bringing about the origin of a new species?
(a) Isolation
(b) Mutation
(c) Natural Selection
(d) Sexual Reproduction
158: Which of the following is a balanced fertiliser for plants?
(a) Urea
(b) Ammonia sulphate
(c) Nitrates
(d) Compost
159: In human body, which one of the following hormones regulates blood calcium and Phosphate?
(a) Thyroxine
(b) Growth hormone
(c) Parathyroid
(d) Glucagon
160: During the freedom struggle, Aruna Asaf Ali was a major woman organizer of underground activity in
(a) Non-Cooperation Movement
(b) Civil Disobedience Movement
(c) Swadeshi Movement
(d) Quit India Movement