Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Input: Consider Input: An object attached to a spring sliding on a frictionless surface is an uncomplicated type of simple harmonic oscillator.

Output: An object attached to a spring sliding on a frictionless surface is an uncomplicated type of what device?

Input: Consider Input: Eyespots do the cells in the front of a volvox typically develop to help swim towards light.

Output: What do the cells in the front of a volvox typically develop to help swim towards light?

Input: Consider Input: Like mitochondria, plastids contain their own dna.
Output: Like mitochondria, plastids contain their own what?