Just to help out:
https://www.khanacademy.org/test-prep/mcat/organ-systems/neural-synapses/v/neurotransmitter-removal
In this case, the card is intending to point at the ‘three main mechanisms’ by which neurotransmitters are removed from the synaptic cleft, which is commonly given by diffusion, breakdown, and reuptake.
Granted, there are other mechanisms (many/most of which are outside the scope of the MCAT), but the typical framing isn’t meant to be exhaustive of all possible routes.
Kaplan Bio Chapter 4, page 156 gives the three listed in the card verbatim, as well as UWorld chapter 12 page 435, so I’m inclined not to add secondary mechanisms outside of the classic Big 3 (also, in general, I will lean toward Kaplan/UWorld over KA for most subjects outside of P/S).
It’s also worth noting that one of the functions of astrocyte feet is, in fact, to aid in reuptake back toward the transmitting synapse, so this point gets a little murky in distinction.
Arguably, the card’s lede should probably be updated to “Give the three main mechanisms by which a synaptic signal is terminated” or something similar in substance/style.
(also the suggested edit adds a fourth step but doesn’t modify the number ‘3’ in the beginning portion of the card, which meh).