Get Lookup Value using REST

Question

Hi,

Facing problem to get Lookup Column value using Rest Api.

My Steps are:

1. Created a list B ,In Title column there are some data.

2.Created a Site Column Name B ,Get value form list B Title Field.

3. Use Site column B in list A as a LookupColumn.

How to get value using Rest Api from list A (column B).

Please Write?