Bathroom basin is blocked

Nearly forgot to have a look at this today!
Water is very slow to drain out of the basin.

Three pipes service the bathroom, can you guess which one was blocked?
With ET guarding the basin and the garden hose (connector removed) shoved in all the way to the end of the pipe I went and turned the back tap fully on.
Back on the ladder manipulated the hose in such a way to try and scrap the sides of the pipe. Repeated that until the water ran clear.

Most of gunky stuff is held together with hair happened to fall between the wall and ladder. No wonder the basin was blocked !!!

ALDI plumbing snake...