Final answer:
A combining vowel is used between word roots in medical terminology to improve pronunciation and clarity. It helps separate the roots and make the term easier to understand and pronounce. For example, in 'electrocardiogram,' the combining vowel 'o' is added between 'electro-' and 'cardi-' to enhance the term.
Step-by-step explanation:
In medical terminology, a combining vowel is used between word roots to improve pronunciation and clarity. It is used when a medical term includes multiple word roots, especially if there is no vowel at the junction between the word roots. This helps to separate the roots and make the term easier to understand and pronounce.
For example, in the term 'electrocardiogram,' the word roots are 'electro-' and 'cardi-' which represent 'electricity' and 'heart,' respectively. The combining vowel 'o' is added between these roots to create 'electro-o-cardi-' to enhance pronunciation and understanding of the term.
Therefore, option b) 'When a medical term includes multiple word roots, a combining vowel is used if there is no vowel at the junction between the word roots' is the correct answer.