Double fertilization is
- fusion of two male gametes of a pollen tube with two different eggs
- fusion of one male gamete with two polar nuclei
- fusion of two male gametes with one egg
- syngamy and triple fusion
Answer
(4) syngamy and triple fusion
Solution
As per NCERT, one male gamete fuses with the egg cell (syngamy) to form the diploid zygote.
The other male gamete fuses with the two polar nuclei of the central cell to form the triploid primary endosperm nucleus (triple fusion).
Two kinds of fusion, syngamy and triple fusion, take place in an embryo sac,
the phenomenon is termed double fertilisation.
Answer: (4)