The term "candid" denotes openness, sincerity, and directness in communication. To identify the closest synonym, the following options are evaluated:
Following this comparative analysis, the word most semantically proximate to "candid" is Frank.
A particle is moving in a straight line. The variation of position $ x $ as a function of time $ t $ is given as: $ x = t^3 - 6t^2 + 20t + 15 $. The velocity of the body when its acceleration becomes zero is: