Question

Under a spreading chestnut-tree

Answer 1

In line two,

B. the second, fourth, and sixth are stressed.

There are four metrical feet in the line.

Explanation:

The stress and unstressed syllables in a line in combination form what is called the line's meter and the individual unit that is defined by the combinations of these unstressed and stressed syllables is defined as the metrical feet of the line.

In line two the stress is not on the first word which is 'The'

then the stress falls on the first syllable of each word after it.

As there are four combinations of unstressed - stressed syllables it has four metrical feet.