Explanation
The correct answer is:
(B) World Environment Day is observed on 5th June.
World Environment Day is a global event celebrated annually on 5th June to raise awareness and promote action for the protection of the environment. It is organized by the United Nations Environment Programme (UNEP) and serves as a platform for individuals, communities, and governments to come together and take positive environmental actions.
Therefore, option (B) World Environment Day is observed on 5th June.