Which spring cue can affect a cat's breeding rhythm?

Answer: Longer daylight

Longer daylight ✓ — Correct! Cats are commonly described as long-day breeders. In intact females, increasing daylight can help shift the hormonal system toward estrous cycling. So spring matters less because the air feels poetic, and more because the light schedule has changed.

More flower smells — Wrong. New plant smells can make a cat investigate, but flower scent is not the main switch for feline breeding rhythm. Smell may change attention or patrol behavior; daylight is the sharper reproductive cue.

The calendar turning March — Wrong. March is a human label. A cat's body is responding to physical signals such as day length and local environment, which is why geography, indoor lighting, and climate can shift the timing.