[单选题]
A material with a mass of m iss(8 iqeydl/p300xz qsyj m)i ; heated. The graph shows the variation of the tempjs0ypmi 8xd3l)0i/eqz(sq ;y ydr( qom jn :fh( y0-gxx8w1e)erature of the material with the 0 eywo(gfym1j q8)r-(nxhd x: energy supplied.
Which one of the following gives the specific heat capacity of the material?
A. $\frac{2Em}{T_2-T_1}$
B. $\frac{Em}{T_1}$
C. $\frac{2E}{m(T_2-T_1)}$
D. $\frac{E}{m(T_2-T_1)}$