For an octahedral complex, which of the following d-electron configuration will give maximum CFSE ?

(a) High spin : d6⇒t2g4eg2  CFSE =−0.4Δo (b) Low spin : d5⇒t2g5eg0  CFSE =−2.0Δo (c) Low spin  :d4⇒t2g4eg0 CFSE=−1.6Δo (d) High spin : d7  CFSE =−0.8Δo