Count the number of sides and corners on each of the shapes. Shape A, B and D all have 4 sides and 4 corner. Shape C is a triangle. It has 3 sides and 3 corners, so it is the odd one out.

Crows are considered to be among the smartest creatures on Earth. They have cognitive abilities at the levels of five- […] ...

Crows can recognize geometric patterns, suggesting that humans aren't unique in understanding shape structure.

Scientists tested crows on their ability to recognize “geometric regularity,” a skill previously assumed to be unique to ...