Final answer:
Cyclopentane has the least angle strain among the given cycloalkanes.
Step-by-step explanation:
The cycloalkane with the least angle strain is cyclopentane. Cyclopentane has a bond angle of about 108°, which is very close to the ideal bond angle of 109.5°. This minimal ring strain makes cyclopentane a more stable compound compared to cyclopropane and cyclobutane.