Final answer:
The answer is d. Aly has an external locus of control.
Step-by-step explanation:
The answer to the question is d. Aly has an external locus of control. An external locus of control refers to the belief that one's outcomes are outside of their control and are instead determined by external factors, such as other people, luck, or chance.
In the given scenario, Aly's decision not to accept being put on a waiting list for an appointment shows that he prefers to have certainty and control over his plans. This aligns with having an external locus of control, as he believes that his appointment cannot be confirmed and is therefore not within his control.