Why do these two surfaces have the same extrinsic topology?

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Reading through the book "The Shape of Space" by Jeffrey Weeks, I encountered the claim that the two surfaces (a) and (f) in the following picture has the same "extrinsic topology" a busy cat
To say that two surfaces have the same extrinsic topology is very loosely defined, and is the same as saying that they can be deformed to eachother. I am having trouble seeing how to resolve the "knot" in (f). Could anyone help me with some visual guidance for why this (f) has the same extrinsic topology as (a)?

** Let me be clear: I agree that the surfaces clearly are homeomorphic. But to me, "extrinsic topology" seems to say that they are isotopic in the $3$-space, or something similar. If so, can anyone explain why this is the case?