"1. A z-score of zero always means  
a. 
the raw score does not exist.
 
b. 
the raw score exists, but is negligible.
 
c. 
the raw score almost never occurs.
 
d. 
the raw score is equal to the mean."

d.

Step-by-step explanation:

Here is an answer I found on the internet (kudos to investopedia.com)

If a Z-score is 0, it indicates that the data point's score is identical to the mean score.

In other words, it's saying that a z-score of zero has a standard deviation of zero.

99

step-by-step explanation:

there has been genes found in the x chromosome of males that have been linked to [homo/hetero]sexuality. in addition to the reign of the x chromosome, a section of chromosome 8 has also been link to, "alot of ppl are so " these facts were proven true after a 2014 study of a gay male and his strait brother. according to newscientist.com,"chromosome 14 and is mainly active in the thyroid, but also the brain. called tshr, it makes a type of receptor protein that recognises and binds to a hormone that stimulates the thyroid. in this way, the gene plays an important role in controlling thyroid function. the fact that tshr seems to be involved in sexual orientation fits with evidence that thyroid function seems to be linked to sexuality."

in conclusion, "ppl are so gay" due to their genetics.