Electrophilic addition of Br2 to 1-butene Steps:

• Straight-chain C4H8 alkene includes 1-butene (CH2=CHCH2CH3).
• Br2 undergoes electrophilic addition across the C=C bond via bromonium ion.
• Br adds to each carbon of the double bond, yielding 1,2-dibromobutane (CH3CH2CHBrCH2Br).
• This structure matches choice C.

Why C is correct:

• It is the vicinal dibromide (Br on adjacent carbons 1 and 2) from anti addition to the terminal double bond, per standard electrophilic mechanism.

Why the others are wrong:

• A: Vicinal dibromide from 2-butene (internal alkene), not 1-butene.
• B: Br on non-adjacent carbons (1,3 positions), impossible from C=C addition.
• D: Br on terminal carbons (1,4 positions), requires no double bond or different reaction.

Final answer: C