Which of the following statements about natural rubber and gutta-percha are correct?

ABoth are polymers of the same monomer, 2-methylbuta-1,3-diene.
BNatural rubber has cis double bonds and gutta-percha has trans double bonds.
CGutta-percha is more elastic than natural rubber.
DThe regular trans geometry lets gutta-percha chains pack closely, making it harder and less elastic.

Answer: A, B, D

Both are 1,4-polyisoprene and differ in alkene geometry. The cis chain is kinked and packs loosely, giving elasticity. The trans chain packs regularly, giving a harder, less elastic material, so the claim that gutta-percha is more elastic is false.

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