Mammals that give birth to fully developed live young are termed
a. monotremes.
b. marsupials.
c. placentals.
d. bird-like.

C. placentals.

Explanation:

The placentals are the mammals which give birth to a fully developed live young individual. These animals are characterized by the presence of placenta which creates a boundary around the fetus. The transfer of food takes place through the tissues of the placenta. Also the wastes are excreted out through placenta.The placental mammals keep their fetus inside the placenta for a complete period of gestation until the complete physical form of the fetus get developed.  

the answer would be 2, if crossing over doesn’t occur 2 out of 4 of the daughter cells will have that allele.

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