Following statements regardinng the periodic trends of chemical reactivity of the alkali metals and the halogens are given. Which of these statements gives the correct picture ?

Question

( A ) The reactivity decreases in the alkali metals but increases in the halogens with increase in atomic number down the group
( B ) In both the alkali metals and the halogens the chemical reactivity decreases with increase in atomic number down the group
( C ) Chemical reactivity increases with increase in atomic number down the group in both the alkali metals and halogens
( D ) In alkali metals the reactivity increases but in the halogens it decreases with increase in atomic number down the group