Step 1: Understand what the figure is testing.
The big picture is made of exactly three shapes, one oval and two triangles, and a rectangular block hides one small region of this picture behind a '?'. We need to work out what that hidden region looks like so that the boundary lines of the oval and the two triangles continue smoothly across it.
Step 2: Look at what enters the missing box from each side.
On the left side of the '?' box, the curved edge of the oval enters the box. This curve has a gentle, constant bend, the same bend you would see on any small arc cut from a circle or oval, so whatever fills the box must continue that curve at the same angle and the same radius of curvature, not a straight edge and not a much larger or much smaller circle.
On the lower side of the '?' box, a straight edge belonging to one of the triangles enters the box at a fixed slope. Whatever fills the box must continue this straight line at the same slope, meeting the visible triangle corner correctly.
Step 3: Test each option against these two requirements.
Option (S) fills most of its box with a large solid half circle. This curve is far too large and has a different radius from the thin arc that enters the box in the original figure, so the curvature does not match, and (S) is ruled out.
Option (Q) has a small triangle whose slanted edge points the wrong way compared to the line entering the box from below, so its straight edge does not continue smoothly into the visible triangle, and (Q) is ruled out.
Option (R) adds an extra triangular sliver in a position where the original figure only shows an oval edge, which would make the total picture show more than the stated one oval and two triangles, so (R) is ruled out.
Option (P) shows a thin curved arc that matches the oval's edge in both direction and curvature, together with a small triangle whose slanted edge lines up with the slope of the triangle edge below the box. Both the curve and the straight edge continue smoothly, so this option completes the figure correctly.
Step 4: Final Answer.
Only option (P) keeps the curvature of the oval and the slope of the triangle continuous across the missing region.
\[ \boxed{\text{P}} \]