How to make an interactive checklist in Rstudio Shiny

I'm trying to build a checklist that will show me different parts of my data in Rstudio using Shiny.

For example: If I check question A: Row 1:2 should show in my table If I check question B while A is still checked: I want to see row 1:2 & 5. If I uncheck question B but check question C while A is still checked: I want to see row 1:2 & 3:4

I made 2 versions but I'm stuck on both

Version 1 (were I'm having trouble with the if statements in the server):

if (interactive()) {

library(shiny)
library(readxl)
Sheet2 <- read_excel("Sheet2.xlsx")
Sheet3 <- read_excel("Sheet3.xlsx")
Sheet4 <- read_excel("Sheet4.xlsx")



ui <- fluidPage(
  title = "Checklist",
  sidebarLayout(
    sidebarPanel(   

      checkboxInput(inputId = "A",
                                  label = strong("A"),
                                  value = FALSE),

      conditionalPanel(condition = "input.A == true", 
                       checkboxInput(inputId = "B",
                                     label = strong("B"),
                                     value = FALSE)),

      checkboxInput(inputId = "C",
                    label = strong("C"),
                    value = FALSE)

      ),
    mainPanel(
      tabsetPanel(
        id = 'dataset',
        tabPanel("Sheet2", DT::dataTableOutput("mytable1")),
        tabPanel("Sheet3", DT::dataTableOutput("mytable2")),
        tabPanel("Sheet4", DT::dataTableOutput("mytable3"))
      )
    )
  )
)

server <- function(input, output) {

  output$mytable1 <- 
    DT::renderDataTable({
      if (input$A){
        DT::datatable(Sheet2[1:2,])}
      if (input$C){
        DT::datatable(Sheet2[3:4,])}
      if (input$B){
        DT::datatable(Sheet2[5,])
      }
    })


  output$mytable3 <- 
    DT::renderDataTable({if ((input$A)){
      DT::datatable(Sheet3[3:4,])}
    })

}

shinyApp(ui, server)

}

And version 2 (were i cant add multiple rows to my groupinput):

if (interactive()) {
library(shiny)
library(readxl)
Sheet2 <- read_excel("Sheet2.xlsx")
Sheet3 <- read_excel("Sheet3.xlsx")
Sheet4 <- read_excel("Sheet4.xlsx")
B3 <- 3:4


ui2 <- fluidPage(
  title = "M&A Checklist",
    mainPanel(
      tabsetPanel(
        id = 'dataset',
        tabPanel("Sheet1", checkboxGroupInput(inputId = "show_vars", 
                                              label = "Questions:", 
                                              choiceNames = c("AAAAAAAAAA","BBBBBBBBBB","CCCCCCCCCCC"), 
                                              choiceValues = c("1","B3","5") )),
        tabPanel("Sheet2", DT::dataTableOutput("mytable1")),
        tabPanel("Sheet3", DT::dataTableOutput("mytable2")),
        tabPanel("Sheet4", DT::dataTableOutput("mytable3"))
    )
  )
)

server2 <- function(input, output) {

  # choose columns to display
  output$mytable1 <- DT::renderDataTable({
    DT::datatable(Sheet2[input$show_vars,])
  })

  # sorted columns are colored now because CSS are attached to them
  output$mytable2 <- DT::renderDataTable({
    DT::datatable(Sheet3[input$show_vars,])
  })

  # customize the length drop-down menu; display 5 rows per page by default
  output$mytable3 <- DT::renderDataTable({
    DT::datatable(Sheet4[input$show_vars,] )
  })

}

shinyApp(ui2, server2)
}

Any suggestions, on how this can be done efficiently?