If an investor had Rs 36,00,000 to invest in any particular single stock, and she could buy the stock only on Monday and sell it off only on Friday, then the stock she should buy on Monday to earn the maximum possible profit during the week is

For each stock:

1. Calculate how many shares can be bought on Monday with Rs 36,00,000
2. Calculate the selling value on Friday
3. Find the total profit

For Marico:

Buy price Monday = $346$

Number of shares = $\lfloor\frac{3600000}{346}\rfloor = 10404$ shares

Sell price Friday = $372$

Total value = $10404 \times 372 = 3870288$

Profit = $3870288 - 3600000 = 270288$

For HUL:

Buy price Monday = $1933$

Number of shares = $\lfloor\frac{3600000}{1933}\rfloor = 1862$ shares

Sell price Friday = $1966$

Total value = $1862 \times 1966 = 3660692$

Profit = $3660692 - 3600000 = 60692$

For ITC:

Buy price Monday = $238$

Number of shares = $\lfloor\frac{3600000}{238}\rfloor = 15126$ shares

Sell price Friday = $253$

Total value = $15126 \times 253 = 3826878$

Profit = $3826878 - 3600000 = 226878$

For Britannia:

Buy price Monday = $3046$

Number of shares = $\lfloor\frac{3600000}{3046}\rfloor = 1182$ shares

Sell price Friday = $3140$

Total value = $1182 \times 3140 = 3711480$

Profit = $3711480 - 3600000 = 111480$

Comparing profits, Marico gives the maximum profit of Rs $270288$, therefore Marico is the correct answer.