Final answer:
The evidence that two segments are allophones of one phoneme is found when they exhibit complementary distribution, occurring in non-overlapping phonetic environments.
Step-by-step explanation:
The pattern that proves evidence that two segments are allophones of one phoneme is a) Complementary distribution. Allophones are variants of a single phoneme that occur in different phonetic contexts wherein one allophone appears in one set of phonetic environments and another allophone appears in a non-overlapping set of environments. For example, the English /p/ sound in 'spin' (which is aspirated and pronounced with a puff of air) vs. 'pin' (which is not aspirated).