Correct

群发

/ qún fà / 
Strokes

Definition

to send to multiple recipients/mass mailout/to occur in a clustered fashion

Example

As an Adjective

large numbers; large scale

1
Yìngduì
应对
qúnfà
群发
xìng
性
shìjiàn
事件

react to a mass event/incident

2
Yùfáng
预防
qúnfà
群发
xìng
性
shìjiàn
事件

prevent a mass event/incident

3
Qúnfà
群发
xìng
性
shìjiàn
事件

mass event/incident

4
Qúnfā
群发
xíngdòng
行动

mass action

As a Verb

group e-mail; mass e-mail; group SMS; group-text