Correct Answer: joking

Solution : The fourth option is the correct choice.

Kidding implies not being serious and is often used when someone is playfully pretending or making a lighthearted remark, while joking means engaging in playful or humorous behaviour, often involving teasing or making light of a situation.

The meanings of the other options are as follows:

• Rocking refers to a rhythmic movement or swaying.
• Mixing refers to the combination of different substances or elements.
• Pleading means making an earnest appeal or request.