Butterflies use their antennae for feeling, smelling, and detecting motion: 

• Antennae: These sensory organs are located at the top of a butterfly's head and are similar to a butterfly's nose. They help butterflies detect chemicals in the air, such as the smell of flowers or a potential mate. They also help with balance and detecting motion. 
• Tactile setae: These are found on the head and abdomen of monarch larvae.

However, the part that develops into the organ that feels is I - Option D