In a replication of the Strange Situation, a developmental psychologist observes a sample of 540 infants. The researcher classifies 324 of these infants as securely attached (Type B), with the remaining infants classified as insecure-avoidant (Type A). Which of the following represents the ratio of insecure-avoidant (Type A) to securely attached (Type B) infants in its simplest form?
3:53:53:5
2:32:32:3
3:23:23:2
18:2718:2718:27