During fertilization in humans,
a) a wave of ca2+ions is released in the fertilized egg’s extracellular space.
b) only one sperm binds to the unfertilized egg.
c) a sperm moves in a directed fashion until it encounters an egg.
d) several sperm pronuclei compete in the cytoplasm to fuse with the egg nucleus.
e) none of the above.

Option B.

Explanation:

Human fertilization is defined as the fusion of a human egg and sperm, occurs  in the ampulla of the fallopian tube.The fusion of sperm and egg results in  the production of a fertilized egg or zygote cell that initiates prenatal development.

During physical intercourse many sperms releases and enters into uterus. although many sperm can bind to an egg, but in normal case only one fuses with the egg plasma membrane and enters into nucleus and the egg cytoplasm.

Thus, the correct option B.

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answer///(c) the maximum number of organisms an environment can support for a long time; i believe this is correct, plz check luck;