An employee’s monthly salary forms an arithmetic progression. If the first month’s salary is Rs 12 000 and the common difference is Rs 350, which of the following expressions gives the salary (in rupees) in the nth month?
(a) 12000+n×350
(b) 12000−(n−1)×350
(c) 12000+(n−1)×350
(d) (n−1)×350