Changing one's mind too quickly

A. Adaptability

B. Instability

C. Versatility

D. Vacillation

Answer: Option D

Solution(By Examveda Team)

One word substitute is Vacillation.

Adaptability: the quality of being able to adjust to new conditions.
Instability: the state of being unstable; lack of stability.
Versatility: ability to adapt or be adapted to many different functions or activities.
Vacillation: the inability to decide between different opinions or actions; indecision.