Tomatoes Or Avocadoes

Riddle: I like indigo but not blue, I like onions but not turnips, I like forms but not shapes. According to the same rule, do I like tomatoes or avocados?

Answer: Avocadoes - I like all things that start with a preposition.

Source: https://www.riddles.com/index.php/627

I like indigo but not blue, I like onions but not turnips, I like forms but not shapes. According to the same rule, do I like tomatoes or avocados? — Tomatoes or Avocadoes by Anonymous Riddle