welcome to the forum. COUNTIFS cannot handle it that way. if it's simply 2014 you want to count, try:
=COUNTIFS(M:M,"pending",C:C,">=1jan2014",C:C,"<=31mar2014")

or with SUMPRODUCT (this will include other years if you have them. dont use whole column for this too)
=SUMPRODUCT((M2:M20="pending")*(MONTH(C2:C20)<=3))