61. Monsoon is caused by
(a) Seasonal reversal of wind
(b) Revolution
(c) Movement of the clouds
(d) None of These
62. Which one of the following is a non-metallic mineral?
(a) Manganese
(b) Magnesium
(c) Gypsum
(d) None of These
63. Yeast is used in making bread because it produces
(a) Carbon Dioxide
(b) Sugar
(c) Bacteria
(d) None of These
64. TV signals are converted into light signals by
(a) Optical fiber
(b) Transistor
(c) Photo diode
(d) None of these
65. The number of spark plugs needed in a diesel engine is
(a) 2
(b) 3
(c) 4
(d) None of these
66. Which one of the following planets orbits around the sun in a clockwise direction from east to west?
(a) Earth
(b) Mercury
(c) Jupitar
(d) Venus
67. Deficiency of which of the following vitamins causes “Night Blindness “
(a) vitamins A
(b) vitamins B
(c) vitamins C
(d) vitamins D
68. Which of the following disease usually spreads through milk?
(a) Plague
(b) Polio
(c) Typhoid
(d) Malaria
69. Epidemiology means
(a) Study of epidemic disease
(b) Study of deficiency disease
(c) Study of medicine
(d) None of These
70. Silk is obtained from
(a) Moth by killing its pupa
(b) Leaves of mulberry plant
(c) Stem of mulberry
(d) None of These