ECONOMICS: The statement, “John buys more of good X as his income increases, ceteris paribus,” means a. John’s purchases of good X are being held constant.
b. John’s income is being held constant.
c. John’s income and purchases of this good are being held constant.
d. John’s income is the only influence that is being allowed to change.
e. The price of this good is being allowed to change.

I am leaning towards D, because "ceteris paribus" means "all things constant", but I am confused about how the question is phrased. I feel like I might be misinterpreting it. Please no fake answers. Thanks in advance! :)
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