The correct option is D heat flow through C = heat flow through B + heat flow through D
Thermal resistance R=R=1KA
(Here w = width)
So, let us write, RA=15 R, RB=160 R
etc and draq a simple electrical circuit as shown in figure
H = Heat current = Rate of heat flow.
In parallel current distributes in inverse ratio of resistance.
Temperature difference (let us call it T)
= (Heat current) × ( Thermal resistance)
TB=HBRB=(316H)(160 R)=30 HR
TC=HCRC=(12H)(60 R)=30 HR
TD=HDRD=(516H)(96 R)=30 HR
TE=HERE=(H)(12 R)=12 HR
Here, TE is minimum. Therefore option (c) is also correct.
∴ Correct options are (a), (c), and (d).