Always true. The sum of the measures of all interior angles add up to 180°.
For example, a right triangle will have a right angle (90°) and two acute angles.
An obtuse triangle has an obtuse angle (with a measure that is greater than 90°) and two acute angles.
The three interior angles of an equilateral triangle have a measure of 60 degrees (acute angles).
An isosceles triangle can have 2 angles with a measure of 30 degrees (acute angles), and an obtuse angle (120°).
Given these examples, we can infer that the correct answer is "Always true."