Final answer:
The term 'life forms' Marty uses appears to refer to animals, plants, or insects. However, without further context, it's hard to provide a definite answer. 'Life forms' generally exclude inanimate objects like cars.
Step-by-step explanation:
Without the context of the broader text, it's challenging to pinpoint what Marty is referring to as 'life forms'. Based on general definition, life forms could mean various organisms that are considered living such as animals, plants, and insects, among others. However, the exact entity that Marty is referring to - whether it's animals, plants, or insects - can only be accurately identified if we know the context in which the statement was made. If we use the given options as a rough guide, the likelihood in a general context is Marty is referring to either animals, plants or insects as 'life forms', not cars which are inanimate objects.
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