A European call option gives the holder the right, but not the obligation, to purchase a specified amount of an underlying asset at a specified price (the strike price) within a specified time period. In this case, the underlying asset is 100 shares of Tesla, Inc., and the strike price is $870 per share. The specified time period is 12 months from now, which is when the option matures. Therefore, at the maturity date, the holder of this European call option has the right, but not the obligation, to purchase 100 shares of Tesla, Inc., for $870 per share. This is the fundamental principle of a call option. The holder can decide to exercise the option and purchase the shares if the market price of the shares is higher than the strike price at the time of maturity. If the market price is lower, the holder can choose not to exercise the option, thereby limiting their loss to the premium paid for the option.

Choice A is incorrect. This choice misinterprets the concept of a call option. A call option does not entitle the holder to make a phone call to inquire about the value of shares. It provides the right, but not an obligation, to buy an underlying asset at a specified price within a specific time period.

Choice B is incorrect. This choice incorrectly suggests that European options can be exercised at any time before expiration. However, unlike American options, European options can only be exercised at expiration.

Choice C is incorrect. This choice describes a put option rather than a call option. A put option gives the holder the right but not an obligation to sell an underlying asset at a specified price within a specified time period.