Which of the following polymers is obtained from $C_2F_4$?

The phenol-formaldehyde resins are formed by polymerisation of phenol and formaldehyde by

Which of the following polymers can be prepared by condensation polymerization?

How is the following resin intermediate prepared and which polymer is formed by this monomer unit?

The correct functional group $X$ and the reagent/reaction conditions $Y$ in the following scheme are:
$X-(CH_2)_4-X \xrightarrow{Y} \text{condensation polymer}$
$(i) \text{ with } HOOC-(CH_2)_4-COOH / \text{heat}$
$(A) X = COOCH_3, Y = H_2 / Ni / \text{heat}$
$(B) X = CONH_2, Y = H_2 / Ni / \text{heat}$
$(C) X = CONH_2, Y = Br_2 / NaOH$
$(D) X = CN, Y = H_2 / Ni / \text{heat}$

For the formation of terylene,the number of moles of ethylene glycol required per mole of terephthalic acid is