Question

circumcenter
incenter
centroid
orthocenter
which center of a triangle is shown in the picture below?

Explanation:

Step1: Recall definitions

Circumcenter: intersection of perpendicular bisectors.
Incenter: intersection of angle bisectors.
Centroid: intersection of medians.
Orthocenter: intersection of altitudes.

Step2: Analyze the figure

The figure shows the intersection of altitudes (lines perpendicular to the sides from opposite vertices).

Answer:

Orthocenter