Shares can be forfeited:

Shares can be forfeited by a company only for non-payment of call money due by the shareholder.

When a company issues shares, it may collect the share amount in installments such as Application Money, Allotment Money, First Call, Second Call, etc. If a shareholder fails to pay the call money (amount due on calls) even after proper notice from the company, the Board of Directors has the authority to forfeit those shares.

Why other options are incorrect:

Failure to attend meetings (Option 2) is not a ground for forfeiture. Shareholders have the right to attend meetings but cannot be penalized with forfeiture for non-attendance.

Failure to repay loan to bank (Option 3) is the shareholder's personal financial matter. The company cannot forfeit shares for external debts of the shareholder.

Shares pledged as security (Option 4) remain the property of the shareholder. Pledging is an arrangement between the shareholder and a lender, and the company has no authority to forfeit shares merely because they are pledged.

The fundamental principle is that forfeiture is a penalty imposed by the company for breach of contract by the shareholder in not paying the amount due on shares. Non-payment of call money is the only valid legal ground for share forfeiture.