Answer:
С3Н6.
Step-by-step explanation:
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In this case, since addition reactions imply that a radical or some radicals are added to the parent chain, we notice that only unsaturated hydrocarbons are able to undergo addition whereas saturated ones undergo substitution reactions as they already have all the carbon bonds bonded to leaving groups.
In such a way, we can rule out C2H6, C3H8 and CH4 as they are all alkanes; therefore, only С3Н6 is able to undergo an addition reaction due to the C=C which is able to lose one of those bonds and allow an incoming radical to get included into the parent chain.
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