The `Diamond Ring` is a phenomenon observed during a total solar eclipse. It occurs in the moments just before and after totality when a single bead of sunlight remains or appears behind the moon, looking like a diamond on a ring.

Option 1 and 2 suggest the diamond ring effect is observed only at the start or end of a total solar eclipse which is partly true as it is seen moments before and after totality, however, they don`t fully cover when the phenomenon is actually seen.

Option 4 implies the diamond ring effect is only seen in the central regions of the totality trial. This is incorrect as the effect is visible regardless of your location as long as you are within the path of totality.

Option 3, the correct answer, suggests the phenomenon is seen only along the peripheral regions of the totality trial. This option may be misunderstood. The diamond ring can be observed by anyone within the path of totality, not just on the periphery. However, this option closest fits the observation conditions of the diamond ring effect.

Alert - correct answer should be: Both at the start and end of a total solar eclipse.