Pollination in Rafflesia is occurred by

a.   carrion flies

b.   elephant

c.   bat

d.   crow

Even after killing the generative cell with a laser beam, the pollen grain of a flowering plant germinates and produces normal pollen tube because

(1) laser beam stimulates pollen germination and pollen tube growth

(2) the laser beam does not damage the region from which pollen tube emerges

(3) the contents of killed generative cell permits germination and pollen tube growth

(4) the vegetative cell has not been damaged.