Answer:
The answer is the 2nd picture: the coccyx bone in humans.
Explanation:
Vestigial Structure:
Structures or anatomical features that do not currently serve a function is the bodily processes of a living organism. Vestiges are believed to have performed active functions in the organism's ancestors throughout its evolutionary history.
Coccyx Bone:
The coccyx or tailbone is an evolutionary remnant of our tree dwelling ancestors. Coccyx has no use in modern humans as we do not need to climb trees.
The coccyx in modern humans serves as an anchor for muscles.
There is one choice missing from this question:
<span>a. narcoleptic fits
b. nightmares
c. apnea episodes
d. night terrors*
The correct answer is "night terrors". Night terrors are intense feelings at the first half of non-REM sleep that is characterized by fear, horror, trembling, shaking. Night terrors are different from nightmares as there are physical effects carried out from night terrors upon waking up such as screaming, crying, and sudden movements.</span>
Compounds are made up of elements.
Elements are the ones we pull straight out from the periodic table.
For example:
H2O, HCl, NaCl, NaOH --> these are all compounds
H, N, B, Ne, Na, Cl, O, K --> these are all elements.
Answer: The probability is 100%.
Explanation: The chromosome X is related to gender. A man carries two different chromosomes (XY) and a woman carries two similar chromosomes (XX). The offspring of a couple will inherited:
- If it is a boy, he inherites the chromosome Y from his father and X from his mother;
- If it a girl, she inherites X from her father and X from her mother;
In the question, the woman is color-blind, which means she carries the recessive alleles: 
The man, on the other hand, is normal, so his X-linked genotype will be:
.
Now, since they have a daughter, she inherited her double X from each of her parents, which means she inherited one
from her mother and one
from her father.
So, the daughter's genotype can only be heterozygotic 
in other words, the probability is 100%.