What could happen if a voltmeter is incorrectly connected in series?

Connecting a voltmeter in series with a circuit can lead to the potential for damage because a voltmeter is designed to measure the voltage difference between two points and ideally has a very high internal resistance. When placed in series, it essentially becomes part of the circuit, introducing this high resistance into the path of current flow, which it is not meant to handle.

Typically, since voltmeters are not designed to carry significant current, a high current flowing through the voltmeter can overwhelm its components, potentially causing overheating or permanent damage. This is particularly critical if the voltmeter is rated for lower current levels than what may be present in the circuit. Thus, the most accurate consequence of incorrect connection in series is the risk of damaging the voltmeter, making this the most appropriate answer.

In other scenarios, such as measuring current, if connected in series, it would not function as intended. The reading may not show zero volts; instead, it may read incorrectly or not at all, depending on the circuit conditions. Hence, while damaging the voltmeter is a primary concern, other outcomes like zero reading or incorrect current measurement stem from the basic mishandling and inappropriate application of the instrument's intended use.