Fill in the blank with the correct verb form from the options given b…

The correct answer is Option (4) → suffering

Present continuous tense:

• It shows an action or state going on now.
• Pattern: is / am / are + verb-ing
  • Helping verb already in the sentence: is
  • Main verb + -ing: suffering
• This sentence: the world is in the grip of climate change at present, so is suffering fits. "Suffer from" means to be badly affected by something.
• Complete sentence: As the world is suffering from the evil clutches of climate change, the role of society is to preserve the environment for future generations.

Why the Other Options are Incorrect?

Option 1: suffer — Incorrect.

• The base form cannot follow "is". "Is suffer" is not English.
• The base form is used after "do", "will", "can" and other modals.
  Example: Crops will suffer if it does not rain.

Option 2: suffers — Incorrect.

• "Suffers" is already a complete present-tense verb. It is used without "is" (The world suffers ...).
• "Is suffers" puts two main verbs together.
  Example: He suffers from headaches in the summer.

Option 3: suffered — Incorrect.

• "Is suffered" would make a passive, but "suffer from" here has no object that could become the subject, so "is suffered from" makes no sense.
• "Suffered" is used for the past tense or after "has/have".
  Example: The town suffered heavy damage in the flood.

Contrast: after "is" only the -ing form makes the present continuous (is suffering). "Suffers" stands without "is", and the base form "suffer" follows modals such as will or can.