Option 1 states that if the Earth`s rotation is reversed, the time at Greenwich when it is noon would be 06.30. This implies that the time at Greenwich would be earlier than what it currently is. However, reversing the Earth`s rotation does not change the time zone of Greenwich, so this option is incorrect.

Option 2 suggests that if the Earth`s rotation is reversed, the time at Greenwich when it is noon would be 17.30. This implies that the time at Greenwich would be later than what it currently is. However, reversing the Earth`s rotation does not change the time zone of Greenwich, so this option is also incorrect.

Option 3 states that if the Earth`s rotation is reversed, the time at Greenwich when it is noon would be 05.30. This implies that the time at Greenwich would be earlier than what it currently is. Reversing the Earth`s rotation does not change the time zone of Greenwich, so this option is correct.

Option 4 suggests that if the Earth`s rotation is reversed, the time at Greenwich when it is noon would be 18.30. This implies that the time at Greenwich would be later than what it currently is. However, reversing the Earth`s rotation does not change the time zone