Error Accessing Set values using the Terraform JSON syntax

Terraform
2

Ok, I got it working with this:

{ 
  "resource": {
      "subdomains_record_valid_test1": {
          "name": "${tolist(resource.aws_acm_certificate.subdomains_cert_test1.domain_validation_options)[0].resource_record_name}",
          "type": "${tolist(resource.aws_acm_certificate.subdomains_cert_test1.domain_validation_options)[0].resource_record_type}",
          "zone_id": "${data.aws_route53_zone.subdomains_zone.zone_id}",
          "ttl": 60,
          "allow_overwrite": true,
          "records":  ["${tolist(resource.aws_acm_certificate.subdomains_cert_test1.domain_validation_options)[0].resource_record_value}"]
         }
    }
}