Correct Answer: Deadly

Solution : The most appropriate synonym for fatal is the fourth option.

Explanation: Fatal is an adjective used to describe something that causes or is capable of causing death.

The synonym should share a similar sense of lethality or causing death, and deadly fits this criterion, as it also denotes something that has the potential to cause death.

The meanings of the other options are as follows:

• Luminous refers to something bright, shining, or emitting light.

• Restorative: This term refers to something that can be restored or renewed, often related to health or vitality.

  Recommended

• Serene: This term describes a state of calm, peace, or tranquility.