Given a text T, and several options, according to the question posed in the text T to choose the most appropriate option from the options as the answer, please directly output the most appropriate option, do not need to output the explanation.

From an investor’s point of view, which of the following equity securities is the least risky?
Option A:Putable preference shares.
Option B:Callable preference shares.
Option C:Non-callable preference shares.

Answer: A