fix comments

clientconn.go

@@ -200,6 +200,7 @@ func WithDecompressor(dc Decompressor) DialOption {
 
 // WithBalancer returns a DialOption which sets a load balancer with the v1 API.
 // Name resolver will be ignored if this DialOption is specified.
+//
 // Deprecated: use the new balancer APIs in balancer package and WithBalancerName.
 func WithBalancer(b Balancer) DialOption {
 	return func(o *dialOptions) {
@@ -219,8 +220,11 @@ func WithBalancerBuilder(b balancer.Builder) DialOption {
 }
 
 // WithBalancerName sets the balancer that the ClientConn will be initialized
-// with. The balancer can not be overridden by balancer option specified by
-// service config.
+// with. Balancer registered with balancerName will be used. If no balancer was
+// registered by balancerName, pick_first will be used.
+//
+// The balancer cannot be overridden by balancer option specified by service
+// config.
 func WithBalancerName(balancerName string) DialOption {
 	return func(o *dialOptions) {
 		o.balancerName = balancerName