The lowest surface air temperature in the southern hemisphere usually occurs during the month of

During June and July.

Explanation:

As on the 21st of June, the sun is at 23.5 north at the tropic of cancer and is far away from the southern hemisphere thus the lowest temperature is recorded in the months of July, within 30 to 40 days as the rays of the sun travel most of the northern side as summer solstices takes place there and the sides are left out.

None of them. they are likely to occur on any plate boundary