American missionary leaders supported imperialism in this era because: O they admired the “pureness if spirit” found in the Filipinos and I the native groups

O they saw imperialism as an opportunity to convert the “heathen” of newly acquired territories

O they thought their involvement would temper the excess zeal and of other imperialism

O American presidents, especially Theodore Roosevelt, strongly pressured them to take that stance

O religious leaders in Europe favored imperialism

they saw imperialism as an opportunity to convert the "heathens" of newly acquired territories.

Explanation:

https://quizlet.com/81433142/the-rise-of-american-imperialism-1890-1913-flash-cards/

Here's a link to where I found the answer

The answer is pretty much contained within the question in this case.  "Subsistence" farming means you're doing enough farming to provide for your own family's needs, but not really any more than that.  Or on a village scale subsistence farming means to be able to provide enough for the subsistence of that village -- for that village to have enough to survive.

So, the main concern of southern Africa's subsistence farmers would be providing for their own family's needs.  They're not trying to produce excess crops for exporting.