Select the phrase/connector from the given three options which can be used to form a single sentence from the two sentences given below, implying the same as expressed in the statement sentence.
Climate change has contributed to the expansion of drier climate zones. The expansion of deserts in the subtropics.
1. When the climate
2. Behind the climate
3. Such as the expansion
1
Only 1
2
Only 2
3
Only 3
4
Both 1 and 2
5
Both 1 and 3