Select the odd letters from the given alternatives?

In the following question, out of the four alternatives, select the alternative which is the best substitute of the phrase.

Choose an option, which can be substituted for a given word/sentence/phrase out of given options.

 A person who is afraid of water

What is the term for a person who believes that the pursuit of pleasure is the highest good?

Select the option that can be used as a one-word substitute for the given group of words.

A person who knows everything

Plunge

She tried to cajole her little brother into eating his vegetables by making silly faces and promising him dessert afterwards.

Give one word substitutes for the following from the choices given below them.

Select the option that can be used as a one-word substitute for the given group of words.

To walk aimlessly

Select the option that can be used as a one-word substitute for the given group of words.

A person having significant experience in an occupation