first of all, good luck for the exams, happy reading.
here is my suggestion for reference books.
Costing- Study mat, compiler, PC Tulsian
FM-Study mat, compiler, PC Tulsian
Income TAx-Study mat (if u have latest copy), supplementary issue, icai (amendments), do not refer to compiler, refer Girish Ahuja (strongly recommended)
Infotech- study mat+compiler more than sufficient
Strategic mgmt- study mat+compiler, spend much time on case study analysis