In second marriages, couples are older and tend to be
a. more realistic
b. more romantic
c. less cautious
d. less flexible

correct option is a.  more realistic

Explanation:

we know that marriage is legally relationship between a husband and a wife

and some for of marriage are

1 Arranged marriage

2 Civil marriage

3 Common law marriage

4 Boston marriage

5 Berdache marriage

and in second marriage

age and experience will be more

so as they age, they have gained experience from their past life

so we can say that in second marriages old couples tend to be more realistic

so correct option is a.  more realistic

c) 50% there are four chromosomes. after crossing over, 2 of the four have been changed. that means any gamete has a 2 in 4 chance or 50% chance of receiving the mutated chromosome.

linnaeus is the father of taxonomy

explanation:

which is the system of classifying and naming organisms. one of his contributions was the development of a hierarchical system of classification of nature. today, this system includes eight taxa: domain, kingdom, phylum, class, order, family, genus, and species.