1.2 Which option below has irrational numbers only? A \( \sqrt{5}, \sqrt{4},-5 \) B \( 0,634 \ldots, \frac{6}{0}, \sqrt{-2} \) C \( \sqrt[3]{7}, \pi, 1,2398 \ldots \) D \( 54,0,5,4^{2} \)

Let's dive into the options! Remember that irrational numbers are those that can’t be expressed as a simple fraction and have non-repeating, non-terminating decimal expansions. In the options given, option C \( \sqrt[3]{7}, \pi, 1,2398 \ldots \) contains only irrational numbers. The cube root of 7 and pi are both well-known examples of irrationals, while 1.2398... may appear to have a decimal representation, but it is actually rational if it terminates. Remember, if you're calculating or identifying irrational numbers, look out for roots of non-perfect squares or known constants like pi! They can help you spot those sneaky irrationals hiding among the whole and rational numbers.