Why might a spinosaur's salt gland be located above its eye?

Answer: Short eye-nose distance

Short eye-nose distance ✓ — Correct! The spinosaur's elongated snout shortened the distance between the eye and nostril, making a supraorbital salt gland with a short duct to the nostril plausible. This shows how facial shape can constrain where a gland can be placed for efficient fluid secretion.

New teeth growing in — Wrong. While tooth replacement is common in dinosaurs, it doesn't explain the location of a salt gland. A salt gland needs a duct to expel salt, and tooth growth doesn't provide such a pathway. The two systems serve different functions.

Stronger neck muscles — Wrong. Stronger neck muscles relate to head support or prey capture, not to salt excretion. A salt gland requires a specific anatomical position with access to the outside, and muscle strength doesn't create that pathway.