Question from the PHP5 test

Nothing because 'true' is not declared as a constant upstream.

Is displayed 'jobprod is in the true!' because '$string' is transtyped to a boolean during the comparison.

Nothing because to compare it is mandatory to use this sense of declaration: 'if (true === $string) {'.

Is displayed 'jobprod is in the true!' because '$string' contains the keyword 'true' and during the comparison an implicit transtyping is performed.

Nothing because '$string' and 'true' are two different types, but the strict comparison operator is used.