Thaddeus Lecture Question -- Moment of Inertia / Deflection

[mpc123]

Question regarding moment of inertia & deflection from Thaddeus' lecture on workbook page 21:

deflection.jpg

"Existing wide flange in warehouse deflects excessively. Which option reduces the deflection the most?"

I am understanding that DEPTH is key and that further away centroids mean more depth against bending, which helps against deflection. However, in the lecture he states option C (T-shape) is better than option B (basic rectangle shape). It appears they have the same depth, and I understand that option C's center of mass is more complicated than a simple rectangle. If I had to choose between B and C on an exam though, I wouldn't know how to make a quick decision. Can someone help explain this in simple terms?

Much appreciated - Thank you!

[lali]

I just saw the video again... Good catch! I think B is better than C, based on his explanation of the centroid.