Which statement is true of semicolons in JavaScript?

The statement that semicolons are essential while combining separate statements in a line is accurate. In JavaScript, semicolons are used to terminate statements, and when writing multiple statements on a single line, semicolons are required to separate them clearly. This prevents ambiguity in how the code is interpreted by the JavaScript engine.

For example, when you write:

let a = 5; let b = 10;

The semicolon indicates the end of each statement, allowing both a and b to be declared in one line. If semicolons are omitted in this context, it can lead to syntax errors or unexpected results, as the interpreter may not correctly infer where one statement ends and another begins.

The other options present various misunderstandings about semicolon usage. While it is often true that semicolons can be optional in certain contexts due to JavaScript's automatic semicolon insertion feature, they are not strictly optional in scenarios where multiple statements are combined on a single line, making this choice the most accurate.