Dyes W,X, Y and Z were analyzed using P as the purest sample of the dye required by a chemist .the result obtained were as shown on the chromatogram below.
![samples of dye on a chromatograph](https://www.easyelimu.com/images/form_3_past_papers/Term_1_2021/end_term_1_2021/samples_of_dye_on_a_chromatograph.PNG)
- What names are given to the lines marked?
- A
- B
- State with a reason the most unsuitable dye for the chemist to use .